Railway traffic controlling apparatus



Patented Feb. 23, 1932 UNITED STATES Parent" OFFICE BERNARD E. OHAGAN, OF- SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed May 11, 1931, Serial No. 536,399. Renewed September 22, 1931.

My invention relates to railway traffic controlling apparatus, and has for an object the protection of such apparatus from damage due to excessive currents.

I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

The present application is a continuation in part of my copending application, filed July 17, 1930, Serial No. 468,550, for Railway traftic controlling apparatus, in so far as the subject matter common to the two cases is concerned.

Fig. 1 of the accompanying drawings is a diagrammatic View showing one form of apparatus embodying my invention. Fig. 2 is a modification of the arrangement shown in Fig. 1 and also embodying my invention.

Referring to Fig. 1 of the drawings, the reference character A designates a railway switch which is actuated by an electric motor M which in the form here shown comprises an armature 1 and a field 2. Operatively connected with the switch are a motor cut-out controller MC and a circuit controller BC. In the motor cut-out controller MC,.contact is made between controller arm 3 and controller contact 4 at all timesexcept when the switch occupies its extreme reverse position, and contact is made between controller arm 3 and controller contact 5 at all times, except when the switch occupies its extreme normal position. In the circuit controller RC, contact is made between arm 6 and contact 7 only when the switch is in the extreme normal position, and contact is made between arm 6 and contact 8 only when the switch is in the extremereverse position. V r

The motor M is controlled in part by a polarized relay WR which comprises a winding 22, a neutral contact 9, and two polar-contacts 10 and 11. The position of the contacts 10 and 11 depends on the direction of the cur-- rentflowing through the relay winding, and the direction of the current depends in turn on the position of a pole changer L. A thermal relay TR comprises a winding 32 having a high resistivity constant anda contact 12, and a thermal relay TN comprises a winding 48 having a high resistivity constant and a 7 contact 13. Contacts12 and 13 remain closed except when an overload occurs due to an ob- .struction'in switch A. Stick relay RS comand contacts 16 and 17. vStick relays RS and N S remain energized at all times except when the thermal relays are open due to an obstruction in switch A and no contact is made between the arm 6 of circuit controller RC and contact 7 or 8.

The pick-up circuit for relay BS is from terminal B of a source of current, through Wire 37, circuit controller arm 6, contact 7, wire 38, wire 39 and'winding 52 to terminal C of the same source of current. The stick circuit for relay BS is from terminal B,

' through wire 42, contact 15, contact 43, wire 44, contact 12, contact 40, wire 41, wire 39 and winding 52 to terminal C. The pick-up circuit for relay NS is from terminal B,

through wire 37, circuit controller arm 6, contact 8, wire 54, wire and winding 53 to terminal C. The stick circuit for relay NS is from terminal B, through wire 56, contact 17, contact 57, wire 58, contact 13, contact 59, wire 60, wire 55 and winding 53 to terminal C;

When polar contacts 10 and 11 are reversed and neutral contact 9 is closed, the reverse operating circuit for motor M is closed; this circuit is from terminal B, through wire 23, contact 9, contact 24, wire 25, wire 26, contact 10, wire 28, armature 1, wire 29, contact 11, contact 30, wire 31, thermal relay winding 32, wire 33, contact 14, contact 34, wire 35, contact 4, controller arm 3, wire 36 and field 2 to terminal C. When the polar con- .tacts 10 and 11 are in normal positions, the

normal operating circuit for motor M is closed, this circuitbeing from terminal B, through wire '23, contact 9, contact24, wire 25, wire 45,.contact 61, contact 11, wire 29, armature 1, wire 28, contact 10, contact 46, wire 47, thermal relay winding 48, wire 49,

contact 16, contact 50, wire 51, contact 5, con-.

troller arm 3, wire 36 and field 2 to terminal C.

In explaining the operation of the apparatus of Fig. 1, I will assume that it is desired to move the switch to the reverse posi tion. The pole changer L is first reversed causing the current to reverse in relay NH. The neutral contact 9 is attracted and polar contacts 10 and 11 move to the right, thus completing the reverse motor circuit and the switch moves to the reverse position. immediately after the switch begins to move, contact 6'? opens, opening the pick-up circuit of relay RS, and this circuit remains open until the switch returns again to its normal position. Assuming that an obstruction occurs in switch A, the motor current will rise above the value necessary to operate the thermal relay TR- and contact 12-4O will open. Stick relay RS will then become deenergized because its pick-up circuit will be open at contact G7, and contacts 14 and 15 drop, thus openin the motor circuit. With the stick relay RS deenergized, it cannot be picked up again until the polarity of relay R has been reversed by reversing pole changer L, and the motor has restored the switch to its normal position. Motor rotation can be reversed when the polar contacts 10 and 11 are reversed because contact 5-3 closes immediately after the start of the movement of the switch away from its normal position. When the switch returns to the normal position, the operation may be repeated as first described.

When it is desired to return the switch to its normal position from the reverse, the pole changer L is again moved to the position in which it is shown on the drawings. T he motor circuit is complete for normal rotation because contact 35 is closed and contacts 16 and 17 are picked up by the energization of stick relay NS through contact 68. Contact 6--S then opens immediately after the switch movement begins. If an obstruction occurs in switch A while the switch is moving to the normal position, the motor current will rise above the value necessary to operate the thermal relay TN, and contact 13-59 will open. Stick relay N S will become deenergized because its pick-up circuit will be open at contact 68, and contacts 16 and 17 drop, thus opening the motor circuit. With the stick relay NS deenergized, it can not be picked up again until the polarity of relay VB has been reversed by reversing pole changer L, and the motor has restored the switch to its reverse position. Motor rotation can be reversed when the polar contacts 10 and 11 are reversed because contact 4-5 closed immediately after the start of the movement of the switch to normal and the reverse motor circuit is complete. When the switch returns to the reverse position, the operation may be repeated as before described.

Referring now to Fig. 2, the arrangement shown in this figure is the same as described in connection with Fig. 1 with the exception that contact 12-4O of thermal relay TR and contact 1359 of thermal relay TN are included in both the pick-up and the holding circuits of stick relays RS and NS, respectively. For example, assuming switch A to occupy the normal position shown, the pickup circuit for relay RS may be traced from terminal B, wire 37, circuit controller arm 6, contact 7, wire 38, wire 41, contact 12, contact 40, wire 39, and winding 52 to terminal C. The stick circuit for relay RS is from terminal B, wire 42, contact 15, contact 43, wire 44, wire 41, contact 12, contact 40, wire 39, and winding 52 to terminai C. Should contact 12-40 of thermal relay TR open due to an abnormal condition such as an obstructed switch, both circuits for relay RS will be deenergized and it will not be possible to pick-up relay RS again until such time as relay TR has cooled sufiiciently to reclose contact 12-40.

The circuits for relay NS may be traced in a manner similar to that just described in connection with relay RS.

One advantage of the apparatus shown in Fig. 2 over that shown in Fig. 1 is that operation of motor M in the same direction as brought about the opening of the thermal rclay contact is prevented completely until this contact has become closed. The closing of this contact is therefore not delayed by impulses of motor current such as would result in Fig. 1 from a failure on the part of the operator to wait for a suiiicient time to permit the thermal relay to cool, before attempt ing another movement of the switch in the same direction.

It will be apparent from the foregoing that with apparatus embodying my invention, when an obstruction occurs in the switch, it is possible to restore the switch to its last operated position immediately and to attempt to operate the movement again in the direction in which it failed as soon as the thermal relay for that direction has cooled so as to close its Contact, thus energizing the associated stick relay.

Although I have herein shown and described only two forms of apparatus embodying my invention, it is understood that vaious changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a railway switch, an electric motor for operating said switch, a normal and a reverse thermal relay each having a heating winding and a normally closed contact, a normal and a reverse stick relay, a circuit controller operated by said switch and having a first contact closed in all positions of the switch except normal and a second contact closed in all positions of the switch er;- cept reverse, a second circuit controller operated by said switch and having a first contact closed in the normal position of the switch and a second contact closed in the reverse position of the switch, a pick-up circuit for said normal stick relay including the second contact of said second circuit controller, a stick circuit for said normal stick relay including the contact of the first thermal relay, a pick-up circuit for said reverse relay including the first contact of said second circuit controller, a stick circuit for said reverse stick relay including the contact of the second thermal relay, a normal operating circuit for said motor including the heating winding of said normal thermal relay and a front contact of said normal stick relay and the first contact of said first circuit controller, and a reverse operating circuit for said motor including the heating winding of said reverse thermal relay and a front contact of said reverse stick relay and the second contact of said first circuit controller.

2. In combination, a railway switch, an electric motor for operating said switch, a circuit controller operated by said switch and having a first contact closed in the nor-- mal position and a second contact closed in the reverse position of said switch, a normal and a reverse stick relay, a normal and a reverse circuit for reversibly operating said motor including a front contact of said nor-- mal and said reverse stick relay respectively, a circuit for energizing said normal stick relay including the second contact of said circuit controller, a circuit for energizing said reverse stick relay including the first contact of said circuit controller, two holding circuits one for each of said normal and said reverse stick relays for retaining said stick relays in their energized condition, and means responsive to the magnitude of the current supplied to said motor for control-' ling the holding circuit for said normal stick relay and the holding circuit for said reverse stick relay, respectively.

3. In combination, a railway switch, an electric motor for operating said switch, a circuit controller operated by said switch and having a first contact closed in the normal position and a second contact closed in the reverse position of said switch, a normal and a reverse stick relay, a normal and a reverse circuit for reversibly operating said motor including a front contact of said normal and said reverse stick relay respectively, a circuit for energizing said normal stick relay including the second contact of said circuit controller, a. circuit for energizing said reverse stick relay including the first contact of said circuit controller, two holding circuits one for each of said'normal and saidreverse stick relays for retaining said stick relays in their energized condition, and means included in each of said normal and said re verse motor circuits and responsive to the magnitude of the current suppliedto said motor for controlling both said energizing and said holding circuits of the stick relay associated therewith.

r 4. In combination, a railway switch, an electric motor for operating said switch, a

circuit controller operated bysaid switch and having a first contact closed in the normalposition and a second contact closed in the reverse position of said switch, a normal and a reverse stick relay, a normal and a reverse thermal relay each having a heating winding and a normally closed contact, a normal circuit for operating said motor including a front contact of said normal stick relay and heating winding of said normal thermal relay, a reverse circuit for operating said motor including a front contact of said reverse stick relay and heating winding of said reverse thermal relay, a circuit for energizing said normal stick relay including the second contact of said circuit controller and the contact of said normal thermal relay, a circuit for energizing said reverse stick relay including the first contact of said circuit controller and the contact of said reverse thermal relay, and two holding circuits one for each of said normal and said reverse stick relays for retaining said stick relays in their energized condition and including the contact of the thermal relay associated therewith.

5. In combination, a railway switch, an electric motor for operating said switch, a circuit controller operated by said switch and having a first contact closed in the normal position and a second contact closed in the reverse position of said switch, a normal and a reverse stick relay, a normal and a reverse circuit for reversibly operating said motor including a front contact of said normal and said reverse stick relay respectively, a circuit for energizing said normal stick relay including the second contact of said circuit controller, a circuit for energizing said reverse stick relay including the first contact of said circuit controller, two holding circuits one for each of said normal and said reverse stick relays for retaining said stick relays in their energized condition, and means responsive to the magnitude of the current supplied to said motor for modifying the energization of said normal and said reverse stick relays by said energizing and said holding circuit associated therewith.

6. In combination, a railway switch, an electric motor for operating said switch, a circuit controller operated by said switch and having a first contact closed in the normal position and a second contact closed in the reverse position of said switch, a normal and a reverse stick relay, a normal and a reverse circuit for reversibly operating said motor including a front contact of said normal and said reverse stick relay respectively, a circuit for energizing said normal stick relay including the second contact of said circuit controller, a circuit for energizing said reverse stick relay including the first contact of said circuit controller, two holding circuits one for each of said normal and said reverse stick relays for retaining said stick relays in their energized condition, and means included in each of said normal and said reverse motor circuits and responsive to the magnitude of the current supplied to said motor for controlling the holding circuit but not the energizing circuit of the stick relay associated therewith.

In testimony whereof I aifix my signature.

BERNARD E. OHAGAN. 

